Edward w



Patented May 30, I899.

E. W. HARDEN'.

comrouun ENGINE.

(Application filed Oct. 24, 1898.)

2 Sheets-Sheet I.

(No Modei.)

Milka um m2 uumm PETERS c0, PHOTO-LITHO WASHINGTON, b, c.

UNITED "STATES EDWARD WV. I'IARDEN, OF CINCINNATI, OHIO, ASSIGNOR -TO FREDERIO'O.

WEIR, E SAME PLACE; LEVI o. o. WEIR, DECEASED.

WVEIR EXEOUTOR OF SAID FREDERIO COMPOUND ENGINE.

SPECIFICATION forming part of Letters Patent No. 625,7 58, dated'ivfay 30, 1899.

' Application filed October 24,1898. Serial No. 694.332. (NomodeL) being acted upon by high-pressure steam, which is compounded upon the largerpistonface.

One of the objects of the present invention is to provide a piston-valve that will control in a novel manner the admission and release of the steam from the high and low pressure ports as well as the final exhaust.

In said PatentNo. 597,433 the steam is admitted from the high pressure port directly into the low-pressure port at the instant of opening said high-pressure 'port and without any means of controlling said steamexcept the high-pressure-port cut-oft; I have found by experience that in order to have a speed yacting engine, it is desirable to release the steam in the high-pressu re cylinder before the piston has reached the end of its stroke. In an engine of the present type if this release is made the steam would be admitted directly ontothe larger face, and hence the piston 3 5 would be acted uponby the steam upon both sides. I overcome this difficultyand accomplish the quick release bythe form of valve here shown. )This consists of three cut-off sections, one controlling the high-pressure 0 port, one the final exhaust-port, and the other the intermediate or skeleton cu t-off interposed between the other two and controlling the intermedia-te low-pressure port. I also utilize the space between the two outside cut-olfs, which are solid disks, to form a reservoir or pocket to receive and hold the steam released from thehigh-pressure port until the time desired to compound it upon the largerpiston. I have found by practical experience that the speed and power of the engine.

Another object of my invention is to employ a steam-jacket on this type of compound enginewhich is continually supplied with live steam direct from the boiler, thereby maintaining the temperature of the chamber of the cylinder approximately the same as the induction-steam in the high-pressure cylinder, and thereby preventing the cooling of the walls of the cylinder when the steam is compounded as low pressure on the piston.

Another object of my invention is to provide improved means. for trapping off the Steam from the jacket.

Another object of my invention is to provide improved means within the valve and valve-chamber for converting the compound engine into a simple engine. Thisis accomplished byintroducingaconverting-valve between the two high-pressure ports of such construction that when said converting-valve is open communication is established between the two high-pressure ports, but; as one of these ports-is alternately opened by the main valve-and when open exhausts its steam on the other end of the piston it follows that direct steam will be acting on and in the same I. have found it to be of material advantage to apply this converting-valve direct to the steam-chestin such a manner as to establish communication readily and at will between the two high-pressureports for converting a compound into a simple engine.

Another object of my invention is to provide an independent pistoncut-off valve, located between the piston cut-olfs, controlling the high-pressure ports of the main valve for controlling the initial ad mission of steam from the induction-ports. i

The various features of my invention are accompanying drawings, making a part of this specification, in which i v Figure l is a diagram showing an engine in side elevation with the eccentrics and starting and controlling levers. Fig. 2 is a central longitudinal sectionthrough the engine. a Fig.

this form of valve gives a better result as to directionon the larger and smaller pistons.

more fully set forth in the description of the 3 is a section on line 0000, Fig. 2. Fig. 4 is a detail view showing a different position of the valve and piston from that shown in Fig.

2. Fig. 5 is a detail view of a convertingvalve. Fig. 6 is a central'longitudinal section through a modification adapted to be used as a stationary engine. Fig. 7 is a section on line .2 2, Fig. 6. A represents a cylinder; A, the heads thereof.

a represents a bridge-wall which serves as a partitionto divide the central portion of the cylinder into two compartments.

B B represent piston-heads mounted upon the piston-rods b.

12 represents a cylinder or drum interposed betweenthe two piston-heads.

represents the steam-chest; D, a pistonvalve mounted therein.

1 represents the induction-port; 2 3, the high-pressure-steam ports; 4 5, the low-pressure and exhaust steam ports and passages.

6- represents a piston cut-off controlling the high-pressure port 2.

7 represents a piston cut-off controlling the H other high-pressure ports 3.

8 9 represent pistons controlling the final exhaust-ports 10.

11 12 represent the ring or skeleton cut-oft controlling the ports 4 5, respectively. This ring or skeleton form is for the purpose of making the space between the. disks 6 and S and 7 and 9 continuous, so as to form pockets or reservoirs in each half of the pistonvalve, for a purpose which will be hereinafter explained.

It will be observed that each one of the ports 2-, 3, 4, and is controlled by a sepatween ports 2 and4 were establishedatthis time, thesame steam would be acting on both sides of the piston and a loss of power rate cut-off or piston-face operated by a common valve-stem. It will be observed also that each. end of the cylinder and piston is a duplicate of the other and has correspondingly-form ed ports, so that a double or duplex engine is produced.

The mode of operation of the valve is as follows: In Fig. 2' the high pressure port is shown as exhausting steam into the low-pressure port 4 at the initial movement of the return stroke, and that port 3 is supplying high-pressure steam to the piston B, and that the low-pressure port 5 is making a final exhaust; through port 10, the valve moving at thisperiod in the same direction as that of the piston. As before stated, it is desirable to release the steam from the high-pressure port before it-is allowedto pass into the lowpressure port to be compounded. In practice thesteam is cut oitsay at the point j shown in Fig. 4)and the steam used expansively for the remainder of the stroke; but it is desirable to release the steam when the piston B has arrived at the position shown infull lines, Fig. 4. If the connection be- I shown in dotted lines.

. opposite to that of the piston. during the time the piston has traveled from water of condensation. any well-known formof construction.

would result. By providing the ring cut-oiI" section 11 port 4 is kept closed until the piston B has reached the end of its stroke, as

The valve in the position shown in Fig. 4 is moving in a direction Port 2 is open the point shown in full lines to that shown in dotted lines, or the end of the stroke, and port 11 is kept closed. The steam from port 2 during this time fills the pocket or reservoir R, which is formed between the piston-disks 6 and 8, and when the valve has traveled in the direction shown by the arrow in Fig. 4 far enough to uncover port 4 the steam from the return stroke of the piston is compounded on the larger piston-face. Of course the opposite end of the engine operates inthe same manner, only-alternately with the part just described.

pocket R and that which is being released by In a compound engine of this type it is desirable to prevent the cooling of the cylinder due to the compounding of the steam on the same surface and to maintain a comparative temperature due to that of the initial heat of the high-pressure steam. To accomplish this, I provide a steam-jacket E, surrounding the cylinder and interposed betweenports 4 and 5 and the walls of the cylinder. This jacket is supplied with high-pressure steam direct from the boiler by means of pipe n, as shown in Fig. 2. condensation, I provide a gutter F, opening into the lower side of the steam-jacket and depending below the same. This gutter is provided with a steam-trap G to carry off the This trap may be of y having a gutter depend: below the jacket and comparatively large area it is partially filled with steam, as well as condensed water, and

assists in maintaining a higher temperature .of thewalls of the cylinder than could be obtained ifthe condensed water were allowed to' rest within the steam-jacket itself.

I'- obtain In order to remove the water of a new result by the use ofthis steam-jacket in a compound engine ofthe typewhich com.- pounds the steam in the same chamber or cylinder in which the high pressure isuti-lized.

When steam is expanded onto the piston, the temperature is reduced by the expansion of the steam, following Mariottes Law of Expansion P'X V 4%. This reduction in temperature due to the compoundingot the steam is materially greater and the initial condensation of the steam is proportionally larger than that due to the expansion of the high-pressure steam. By the use of a steam-jacket as herein shown and described, the inner wall-ofthe cylinder is maintained approximately at the temperature of the high-pressure steam and consequently the expansion of the lowpressure steam instead ofcooling the cylinder-surface to a larger extent than hitherto obtained, is heated by the walls of the cylinder,

' link-arm 19.

' engine.

' thus preventing condensation, and maintaintion in the cylinder occurs in the gutter F within the steam-jacket, and a very high useful eifect is obtained from the engine.

I have found by actual experiment that the amount of live steamemployed in the steamjacket and ultimately condensed in the gutter is very materially less in amount of condensed water than the Water of condensation in thecylinder itself when nosteam-jacket is employed.

It is sometimes desirable, and especially in locomotives, to convert a compound into a simple engine for the purpose of starting a train or going up a steep grade. I accomplish this by the converting-valve, applied direct in the steam-chest. This converting-valve is shown in Figs. 3 and 5, and the apparatus for operating the sameis shown in Fig. 1-. It will be observed in Fig. 2 that the ports 2, 3, 4,.

and 5 in the cylindrical steam-chamber each have an annulus upon the interior walls of the chest, of equal area to the several portopenings of the steam-chest, and these are indicated by figures 2, 3, 4E, and 5, upon one side of the steam-chest. I mount pipe extensions e e, which pipe extensions extend into the walls I of the steam-chest and communicate with the-high-pressure annulus 23. J represents an elbow-pipe rigidly secured to the pipes c e. K represents a plug-valve; 9, an opening formed through the plug. When this plug is turned so that its opening is coincident with the pipe-passages, live steam is admitted from port 3 into port 2, or vice versa,

andwhen piston B is receiving direct steam; piston B is receiving-steam through port 4' It follows that both pistons B, B are being acted upon by the high-pressure; steam and the engine is working simple. In} Fig. l I have shown the method of operating this convertinglever. 13 represents the or-. dinary eccentrics; 14, the ordinary links; 15,

from port 2.

the connecting-rod for operating'the mainvalve stem l6. 17 represents the bell-crank lever for reversing the main valve. resents a fulcrum upon which is pivoted a 20 represents a connecting-rod passing through and connecting with a duplicate link-arm on the opposite side of the 21 represents a connecting-rod operated by lever 22. 23 represents a connecting-rod hinged to arm 19 and to crank-arm 24, which crank-arm is connected to the stem of plug-valve K, as shown in Figs. 3 and 5. By moving the lever 22 plug-valve K is rotated one-fourth of a revolution to open and close the same.

In Fig. 6 I have shown the form of piston- IS repvalve especially designed for stationary engines, or that type of engine employing an automatic cut-off. It is desirable to employ a piston-cut-ofi valve, and this is accomplished in the following'manner: 25 represents the induction-port for admitting steam into the high-pressure ports 2 and 3. 26 represents a piston cut-off located between the pistondisks 6 and 7. The main piston-valve employs a hollow valve-stem 27, connected to the hub of disk 9. 29 represents the pistonrod of the cut-off valve, which journals and reciprocates within the sleeve piston-stem 27. 30 represents the guide for the slide 31; 32, the wrist-pin thereof. 33 represents the guide of the cut-off valve, 34 the slide, and 35 the wrist-pin of slide 34.

It will be observed that the construction of the cylinder piston-ports, piston-valve, and disk cut-eds shown in Fig. 6 is the same as that shown in Fig. 2 except the change of location of the valve-rod and its connection.

In the cut-0E valve it is preferred to have the valve-rod centrally located, so as to better connect the duplex sections of the main valve, which is accomplished by means of the rods 36, that connect disks 6 and 7 together. This provides space for the independent movement of the cut-0E valves between said disks.

It will be observed that each piston of my engine and the controlling parts thereof are duplicates one of the other and that consequently the main valve is a duplex pistonvalve, the novel features of which consist in interposing a ring or skeleton cut-01f between the disk and cut-off of the high-pressure port and final exhaust-port, and that this ring controls the low-pressure port located between the other two ports. I believe I am the first to provide the three cut-oifs for each of said ports and the first to employ the space between the two disk cut-ofis for a temporary pocket or reservoir, and I also believe I am the first to employ a converting-valve applied direct to a steam-chest to connect and disconnect the high-pressure ports of a compound engine, each' of which admits steam into a duplex cylinder to operate upon pistons connected to a common rod, thereby obtaining a highly-useful effect. I also believe I am the first to employ a steam-jacket in an engine supplied with steam direct from the boiler, which is adapted to reheat the steam in the act of compounding, and I do not wish to limit myself in these respects to the specific devices herein shown and described.

I have shown in the drawings the gutter F of two steam-jackets connected together and a trap L connected to a pipe which taps each end of said gutter. It is obvious that the gutters of each of said'st-eam-jackets need not be connected and that each can be emptied by a separate trap, if desired.

Having described my invention, what I claim is- 1. In a compound engine having a duplex cylinder and a double piston for each cylinder, the opposing faces of each of which are of diiferent areas, a live-steam port leading to the smaller piston-face, a low-pressure port leading to the larger piston-face, and an outside exhaust-port in each cylinder, the combination of a cylindrical steam-chest, a piston-valve, operating therein, and having a cut-off section for the high-pressure port, for the low-pressure port and for the exhaustport, whereby the admission and escape of vthe steam of each of said ports is controlled by its respective cutolf, substantially as specified.

2. In a compound engine having a duplex cylinder and a double piston for each cylinder, the opposing faces of each of which are of different areas, a live-steam port leading to the smaller piston-face, a low-pressure port leading to the larger piston-face, an outside exhaust-port in each cylinder,,the combination therewith of a cylindrical steam-chest, the piston-valve operating therein, and having a disk cut-oif section for the high-pressure port, a separate disk section for the exhaustport, and a ring cut-ofi section intermediate between the said disk sections, and controlling the low-pressure port, and a temporary steam-receiving pocket formed between said outside disk cut-oft sections for receiving steam from the high=pressure port in the manner substantially as described.

3. In a compound engine having a duplex cylinder and a double piston for each cylinl der, the opposing faces of each of which are of difierent areas, a live-steam port leading to the smaller piston-face, a low-pressure port 1 leading to the larger piston-face, and an exhaust outside port in each cylinder, the combination therewith of a cylindrical steamchest, and a piston-valve having cut-off sec- 'tionscontrolling each of the said ports at each end of the steam-chest and operated by a common valve-stem,substan'tially as herein speci- 4:. In acompound engine having a duplex cylinder and a double piston for each cylin- -der,gthe opposing faces of each of which are of different areas, a live-steam port leading to the smaller piston-face, a low-pressure port leading tothe larger piston-face, and an outside exhaust-port in each section,-the combination therewith of a steam-chest, a duplex valve, provided with separate cut-off sections for controlling each steam-port and a converting-valve located in branch extensions of the two high-pressure steam-ports, means for operating said valve whereby live steam may 5 be at pleasure simultaneously admitted intoder, the opposing faces of each of which are of different areas, a live-steam port leading to the smaller piston-face, a low-pressure port leading to the larger piston-face, and an out side exhaust-port in each section, the combination therewith of a steam-chest, a duplex valve provided with separate cut-off sections for controlling each steam-port and a con verting-valve located in branch extensions, tapping the two high-pressure ports, and extending outside of the steam cylinder and connected together, a cut=off valve located at the junction of said extensions and meansfor operating the same whereby live steam admitted into one of said ports may be directly admitted through said extension into the other live-steam port, substantially as speci= fied.

6. In a compound engine having a duplex cylinder and a double piston for each cylinder, the opposing faces of each of which are of different areas, a live-steam port leading to the smaller piston-face, a low-pressure port leading to the larger piston-face, and an'outside exhaust-port in each cylinder, the combination therewith of a steam-chest, a plural cut-off main valve provided with a hollow valve-stem and having cut-off sections for controlling the high-pressure and exhaust ports and an induction-port in the steam-chest located between the high-pressure ports and a cut-off valve controlling said inductionports and operated by a valve-stem extending through the hollow stem of the main valve, substantially as specified.

7. Ina compound engine having a duplex cylinder and a double piston for each cylinder, the opposing faces of each of which are of difierent areas, a live-steam port leading to the smaller piston-face, a low-pressure port leading to the larger piston-face, and an outside exhaust-port for each cylinder, the combination therewith of a cylindrical steamchest, having a main piston-valve having a plurality of cut-ofi sections each controlling its respective ports andconnected to a hollow valve-stem, an induction-port located between the two high-pressure ports and a piston-cut-off valve controlling said inductionport by means of a valve-stem reciprocating in the hollow stem of the main valve andconnected to an independent wrist-pin, substantially as specified.

8. In a compound engine having a duplex cylinder and piston, a live-steam port, a lowpressure port and'an exhaust-port in each cylinder,the combination therewithof an annu lar steamjacket formed in the walls of the cylinder, a section of which is interposed .be-

tween the low-pressure port and the inner petained at a heat above the condensing-point and the Water of condensation of the engine is deposited in the steam-jacket outside of the piston-chamber, substantially as specified.

9. In a compound engine of the described type an annular steam-jacket, formed in the walls of each cylinder a section of which is inside of the low-pressure ports and provided with a gutter on one side thereof extending outside of the walls of the cylinder for receiv ing the water of condensation and means for 10 trapping the Water out of said gutters, substantially as specified.

In testimony whereof I have hereunto set my hand.

EDWARD W. HARDEN. Witnesses:

OLIVER B. KAISER, W. R. WVOOD. 

